HAIR AND UNDER-FUR cular arrangement of the individual hairs among mammals; they are not by any manner of means scattered without order, but show a definite and regular arrangement, which varies with the animal. For instance, in an American Monkey (Midas), the hairs arise in threes—three hairs of equal size springing from the epidermis close together; in the Paea (Coelogenys) there are in each group three stout hairs alternating with three slender hairs. In some forms a number of hairs spring from a common point: in the Jerboa (JDipusf) twelve or thirteen arise from a single hole; in Ursus aretos there is the same general plan, but there is one stout hair and four or five slender ones. There are numerous other complications and modifications, but the facts, although interesting, do not appear to throw any light upon the mutual affinities of the animals. Allied forms may have a very different arrangement, while in forms which have no near relationship the plan may be very similar, as is shown by the examples cited from Ur. Meijerle's paper. The groups of hairs, moreover, have them- selves a definite placing, which the same anatomist has compared with the disposition of the bundles of hairs behind and between the scales of the Armadillo, and which has led him to the view that the ancestors of mammals were scaly creatures—a view also supported by Professor Max Weber,1 and not in itself unreason- able when we consider the numerous points of affinity between the primitive Mammalia and certain extinct forms of reptiles.2 The hairs are greatly modified in form in different mammals and in different parts of their bodies. It is very commonly the case that a soft under-fur can be distinguished from the longer and coarser hairs, which to some extent hide the latter. Thus the " sealskin " of commerce is the under-fur of the Otaria if.rsina of the North. The coarser hairs may be further differentiated into bristles ; these again into spines, such as those of the Hedgehog and of the Porcupine. Again, the •flattening and agglutination of hairs seems to be responsible for the scales of the Manis 1 ** Bemerktmgen iiber den TTrsprang der Haaro," Anat, *4nxf 1893, p. 413. a See for tills matter, p. 90. Dr. Bonavia lias recently advanced (Stitd'i&s -in JBv&lutivn) Ijondon, 1805) the somewhat fantastic view that the pigment-patches of Carnivorous and oth-or •mammal** are a reminiscence of an earlier scaly condition. There i« no direct evldwnco that the primitive mammals wore scaly, nor are the Monotremaia or Marsupials furninhed with any more traces of stich, a con- dition titan are other mammals » and they are the most lowly organised of existing Mammalia.